The Reaction F + H 2 → Hf + H. In: Prigogine I, Rice SA, editors. Advances in Chemical Physics. Hoboken: John Wiley & Sons, Inc.; 1980. pp. 229-68. [DOI: 10.1002/9780470142608.ch4]

Theories of reactive scattering

This paper is an overview of the theory of reactive scattering, with emphasis on fully quantum mechanical theories that have been developed to describe simple chemical reactions, especially atom-diatom reactions. We also describe related quasiclassical trajectory applications, and in all of this review the emphasis is on methods and applications concerned with state-resolved reaction dynamics. The review first provides an overview of the development of the theory, including a discussion of computational methods based on coupled channel calculations, variational methods, and wave packet methods. Choices of coordinates, including the use of hyperspherical coordinates are discussed, as are basis set and discrete variational representations. The review also summarizes a number of applications that have been performed, especially the two most comprehensively studied systems, H+H2 and F+H2, along with brief discussions of a large number of other systems, including other hydrogen atom transfer reactions, insertion reactions, electronically nonadiabatic reactions, and reactions involving four or more atoms. For each reaction we describe the method used and important new physical insight extracted from the results.

CROSSED-BEAM STUDIES OF REACTION DYNAMICS

▪ Abstract  This article reviews recent progress in our understanding of gas-phase neutral reaction dynamics as made possible by improvements in the crossed molecular beam scattering technique for measuring reactive differential cross sections. A selection of crossed-beam studies on systems that play a fundamental role in our basic understanding of reaction phenomena are discussed to illustrate the capabilities of the experimental method. The examples include benchmark atom-diatom abstraction and insertion reactions, and four-atom radical reactions for which state-to-state, state-resolved, or state-averaged differential cross sections have recently been measured. The results are discussed in the light of the latest related theoretical developments regarding the treatment of potential energy surfaces and the dynamics of the systems. Recent results on crossed-beam studies of chemically relevant reactions of carbon, nitrogen, and oxygen atoms are also reviewed, and the latest developments in the technique are noted.